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Hi all, I have an 81 (original owner) that just came out of a long storage, I last had it on the road in 2002, but periodically took it out to start up , wash it.....
.I am having trouble keeping fuel in the gas filter. I put a new Wix see through gas filter on it and the truck will idle. put some load on it and the fuel filter starts emptying out, ( it will sit with a 1/4" or less of fuel in it at idle). At idle it will run for hours, but the pump could barely keep the filter wet, I went ahead and changed out the mechanical pump, and still same issue. So I think the problem is from the filter and back. I blew out the main fuel line off the filter to the gas tank and it pressurized the tank, so I removed the gas cap to relieve the pressure.
Could this be an Evap problem ? I tied to fill the tank, and it would not fill w/o spilling,( which leads me to the Evap). The carb was professionally rebuilt 2 years ago. I have my factory 81 HI Lux Toyota manual, but they don't really get into this trouble shooting. The gas gauge reads empty, but there is gas in it, I just don't know the exact amount ( not to sure if tank is sending correctly).
I traced back all of the fuel lines and nothing is rotted, or kinked. Mine has just 1 charcoal canister.
So I know the fuel is good, because the truck will idle, the pump is new, the 3 short fuel lines that come off the top of the fuel pump are new.
Any ideas?